Havasu Falls

The water is that colour because it comes out of the ground already saturated with calcium carbonate, which precipitates as travertine and both lines the streambed and scatters light - the same process that builds the terraces the falls pour over. This is the Havasupai Reservation, not the national park, and the tribe controls all access: permits are sold online on a release date, sell out within minutes for the year, are non-refundable and non-transferable, and cover a mandatory three-night stay. The trailhead is a long drive from anywhere, the walk in is sixteen kilometres descending about seven hundred metres, and the walk out is the same in reverse. Flash floods have swept the canyon and forced evacuations more than once.

What's there

• Travertine falls in blue-green water - from carbonate-saturated springs.
• A sixteen-kilometre walk in - descending seven hundred metres.
• Permits sold once a year - gone in minutes, three nights mandatory.
• Havasupai land - not the national park, and governed by the tribe.

When to go

March to May and September to October, if you hold a permit. Three days minimum.

Things to know

Without a permit you cannot go, and permits are extremely hard to get. The walk out is a serious climb in heat. Flash floods have required helicopter evacuation. This is a community's home - visitor conduct rules are strict and enforced.

Nearby

Grand Canyon National Park is east; Peach Springs is south.

Key facts